Key battles have shaped history since time immemorial. This handy reference work spotlights 100 of the world's most important military confrontations, from 1469 B.C.-A.D. 1991.

What if the Saxons had triumphed over the Normans in the Battle of Hastings? If Washington had lost the Battle of Trenton? If Lee had won at Gettysburg? If the Germans had held the Allies at bay in Normandy? The world would be a much different place today.